Sifters may be used by homeowners to separate larger particles of dirt or fertilizer for easier spreading and more uniform application. Yard debris, such as edgings from mulched beds and other small scale excavations, may be recycled by extracting the rocks and clumps of undesirable sod from the good soil.
Non-powered sifters for individuals have been in use for many years. One type of sifter includes a rectangular wooden frame of about two feet in length per side. A wire mesh is secured to the frame and extends across the opening of the frame. The user deposits the material to be sifted (e.g., soil) on the top surface of the mesh and then shakes the sifter frame back and forth. Clumps of soil, rocks, and other objects that are larger than the size of the mesh openings are retained on the mesh; the remaining soil and smaller objects pass through the mesh. A similar sifter is used for artifact sifting in archaeology, where the sifter has a fine mesh and where the frame is a circular, wooden hoop with a diameter of about 12 to 16 inches.
Another sifter for garden use is the Scheppach rs150 hand sifter for soil and compost. The sifter includes a cylindrical metal body extending vertically and supported on three legs attached to the cylinder. The cylinder has a diameter of about 16 inches. A metal mesh is welded to the bottom opening of the metal body. A bar is connected to and extends over the top of the cylindrical body. A hand crank is attached to the bar and drives a rotating blade across the top surface of the wire mesh to apply pressure to the soil and force it through the mesh. The user deposits soil into the cylindrical body, then rotates the crank to move the blade through and over the soil. As the blade rotates across the wire mesh, soil is distributed across the mesh where undersized material can fall through openings.
On a larger scale, powered sifters may be used by commercial excavators at job sites to sift soil on a much larger scale. An excavator or bucket loader will load many yards of soil onto the sifter grid and a large motor will separate the usable dirt from the rocks. The sifted dirt is then loaded onto large dump trucks to be delivered to nurseries and other outlets for sale to retail or commercial landscaping customers.
For example, U.S. Pat. No. 6,029,822 to Skoropa (issued Feb. 29, 2000) discloses a drive system for a vibratory screening device useful for separating undersize and oversize materials in a loam mixture. A box frame supports a vibratory drive system and a screen assembly. An engine drives a horizontal eccentric shaft that is connected to the vibratory drive system, where the shaft has an axis of rotation that oscillates relative to the frame as the shaft is rotated. The screening device is used for separating heavy materials that are dumped onto the vibratory screening device using a wheel loader, skid steer, or conveyor.